Perlite

Perlite is a naturally occurring volcanic glass that forms when obsidian is exposed to water and heat, causing it to expand and become light and porous. When heated to high temperatures in industrial furnaces, perlite pops like popcorn, creating tiny air-filled bubbles throughout the material that make it exceptionally lightweight and useful for insulation, filtration, and as a soil amendment in gardening. Because of its low density, high porosity, and inert chemical properties, perlite has become one of the most versatile minerals in construction, agriculture, and manufacturing industries worldwide.